<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>'
<style>
    .box{
        width: 95%;
        max-width: 1600px;
        display: grid;
        grid-template-columns: 1fr 1fr 1fr;
        grid-template-rows: 100px 100px 100px 100px;
        gap: 80px;
    }
    .item {
        background-color: red;

    }
</style>
</head>
<body>
    <div class="box">
        <div class="item" >1</div>
        <div class="item" >2</div>
        <div class="item" >3</div>
        <div class="item" >4</div>
        <div class="item" >5</div>
        <div class="item" >6</div>
        <div class="item" >7</div>
        <div class="item" >8</div>
        <div class="item" >9</div>
        <div class="item" >10</div>
        <div class="item" >11</div>
        <div class="item" >12</div>
        <div class="item" >13</div>
        <div class="item" >14</div>
        <div class="item" >15</div>
    </div>
</body>
</html>